The 830 has several software sided advantages the 530 does not offer.
I wrote about it here:
https://www.trainerroad.com/forum/t/anybody-trouble-with-edge-530-buttons/59714/7
Recently I very much appreciated the 830 with its very easy way to switch to a different track on the go during an active session. As we all know Garmin for some reason does not allow to change any sync with the phone during active rides… it is off and therefore tracks assembled on the phone do not reach the device unless you end the session… anoying
So the only way to change the track on the go is via Course Creator on the device itself.
with the 830’ touchscreen it is very easy to set up a new track via Course Creator and follow it without ending the ongoing ride. I tried that on the 530 before but the button simply make it supercomplicated and it takes forever.
I would not change back to a 530.